MQ-3 Alcohol and Ethanol Gas Sensor Module – 5V Analog Digital Output

The MQ-3 Alcohol and Ethanol Gas Sensor Module is designed for detecting alcohol vapors in air, making it suitable for breathalyzer and alcohol monitoring applications. It operates at 5V DC and provides both analog (0–5V) and digital (TTL) outputs for flexible integration with microcontrollers. The onboard comparator and adjustable potentiometer allow threshold calibration for reliable detection. Built for stable performance, it supports Arduino and other 5V development platforms. Ideal for breath alcohol testers, safety systems, and embedded gas detection projects.

• MQ-3 gas sensing element for alcohol detection
  
• Operating voltage 5V DC
  
• Analog output 0–5V proportional to concentration
• Digital TTL output with adjustable threshold
  
• Onboard LM393 comparator circuit
  
• Adjustable sensitivity via potentiometer
  
• Power indicator LED
  
• Digital output status LED
  
• Preheat time approximately 20 s
  
• Compatible with Arduino and 5V MCUs
  
• Compact PCB design 32 × 22 mm
  

• Sensor Type: MQ-3 Semiconductor Gas Sensor
  
• Target Gas: Alcohol, Ethanol Vapors
  
• Operating Voltage: 5V DC
  
• Operating Current: ≤ 150 mA
  
• Analog Output Voltage: 0–5V
  
• Digital Output Voltage: 0V or 5V TTL
  
• Detection Range: 0.04–4 mg/L Alcohol (approx.)
  
• Preheat Time: ≥ 20 s
  
• Comparator IC: LM393
  
• Operating Temperature: -10 °C to 50 °C
  
• Module Dimensions: 32 × 22 × 18 mm
  
• Compatibility: Arduino, AVR, PIC, STM32 (5V logic)

• MQ-3 Data Sheet
• MQ-3 User Manual
• Building Breathalyzer using Arduino
• Building Breathalyzer

• MQ3 SENSOR with Arduino UNO board - How to work MQ3 SENSOR (Code and circuit diagram)